In Karayollari, a Kurdish-majority neighborhood in Istanbul, the locals are seething. On Dec. 28, Turkish warplanes flying over Uludere, close to the Iraqi border, rained bombs on what pilots believed to be a column of militants from the Kurdistan Workers' Party (PKK), a Kurdish separatist group. It turned out to be civilians smuggling diesel. Thirty-five people lost their lives in the attack. Karayollari might be over a thousand miles away from Uludere, but the impact of the tragedy on local Kurds is palpable. Since the beginning of the year, protests have erupted there and in surrounding neighborhoods on an almost daily basis.

The recent surge in fighting between the Turkish military and the PKK  punctuated by the Uludere massacre and the killing of 24 Turkish soldiers by the Kurdish rebels two months earlier  has revived fears of an imminent return to the bloody 1990s, when civil war ravaged Turkey's Kurdish-populated southeast. Today, not only does the violence threaten to intensify, it also threatens to spread. With interethnic tensions and clashes on the rise across the country, there is increasing evidence that Turkey's cities, home to millions of Kurds, may be becoming a new front in the conflict.

"Unless the government can manage the situation, there is a risk of ethnic tension at the societal level," says Nihat Ali Ozcan, a retired army officer. In Istanbul, the Turkish city with the largest population of Kurds  with an estimated 2 million to 4 million out of the city's total of 12 million  the risk of conflict appears more acute than anywhere else.
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Mustafa, like many residents of Karayollari, hails from Siirt, a city in the southeast. He arrived in Istanbul about 20 years ago, he says, part of an entire generation of Kurds displaced by the Turkish military's scorched-earth tactics. We meet at a local teahouse among men in plaid sweaters and leather jackets playing backgammon, fingering Islamic prayer beads and blowing vast rain clouds of smoke from contraband cigarettes. Roj TV, considered a PKK mouthpiece, banned in Turkey and broadcast via satellite from Denmark, blares in the background. Conversation is sparse. If and when it takes place, it is almost exclusively in Kurdish. (As late as two decades years ago, speaking that language in public was considered a crime.) The choice of programming, as well as the men's blissful disregard of Turkey's two-year-old smoking ban, is telling. Karayollari, an hour's bus ride from the city center, is something of a world onto itself. "The cops don't venture here," Mustafa says, "unless it's to arrest activists or to crack down on protests."

In the past few months, dozens of Karayollari locals have been detained in raids against the Union of Kurdistan Communities (KCK), which the authorities regard as the PKK's urban wing. (The PKK itself is considered a terrorist organization by Turkey, the U.S., and the European Union.) This has not deterred other residents from staging protests. With stations like Roj TV reporting nonstop from the Kurdish areas of Turkey, Mustafa says, "people here are more aware of the Kurdish problem. Whenever we feel our people are being suppressed, we react." A young man sitting at our table helpfully points out that the streets around the teahouse make good getaway routes during battles with the police. "If something goes down in the southeast today," Mustafa says, "something will go down in Karayollari tomorrow."

On the other side of a highway overpass that separates Karayollari from Gazi Mahallesi, an ethnically mixed neighborhood reputed to be one of Istanbul's poorest and most dangerous, signs of tension are rife. On the road leading up to the local police station, ATMs belonging to the local branch of Ziraat Bankasi, a state bank, have been vandalized in protests that have united Kurds, radical leftists and anarchists. The police station itself  perched atop a hill overlooking the neighborhood, an enormous Turkish flag raised overhead  looks like a fortress. Antigovernment graffiti is everywhere. "Revolution or Death, the Only Solution for Kurdistan," reads one sign, spray-painted onto the side of a building. Mazlum Poyraz, a student, says that municipal buses have been pelted with stones so often the transport authority no longer routes its modern, air-conditioned vehicles through the area.
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In this Istanbul neighborhood, as in the southeast, poverty and unemployment help nourish the cycle of violence. So does urban displacement. These days, Gazi is buzzing with rumors that a neighboring shantytown, home to Turks and Kurds, may soon be leveled to make way for an upscale housing development. In Karayollari, this is already fact. Within a short walk from the teahouse, a large slum area has been razed, its Kurdish and Roma residents evicted, to make way for Avrupa Konutlari, a gated community comprising more than 30 high-rise buildings.

To the Kurds of Karayollari, the adjacent high-rises, home to mostly middle-class Turks, have become something of a symbol. "Avrupa Konutlari, for us, is the state," says Mustafa. On some occasions, the buildings themselves have come under attack. When Turkish soldiers die in combat against the PKK, "many of the Turks living there hang national flags from their balconies," says Sercan, an abbreviated version of his name tattooed in ink across his knuckles. In response, he says, Kurdish protesters from Karayollari "sometimes throw stones or Molotov cocktails at their windows."

"With these buildings, once again they're uprooting the Kurds," says Mustafa. "When the state does this, when it creates these kinds of divisions, people from our part of the neighborhood, they get upset. So if you're in a protest and you have a stone in your hand, you'll throw it at one of the skyscrapers."

More unrest may soon be in store. On Tuesday, a Danish court will rule on whether to shut down Roj TV, the Kurds' biggest television station, on account of its links with the PKK.

The conflict in the southeast, which began with a PKK insurgency in 1984, has so far claimed around 40,000 lives, victims of armed battles, terrorist attacks by the Kurdish rebels and often savage reprisals by the Turkish army and security forces.